Ever since last year when I was first diagnosed with MG my voice too had been greatly affected. Every single day I have speech problems, there are times when I try to speak it takes my breath away. It sounds nasal, then it's muffled, then its both. I try to talk slower, to get my words sounding right but I know from experience that this is vary hard to deal with. I almost always need someone to talk for me when I need to call anyone. Its hard but my thought is, there is always tomorrow.